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Essex is a town in Middlesex county in Connecticut. It was formed in 1852 from the following town or towns: Saybrook. Essex is a part of the Essex probate district and has been since 1853. Saybrook was/were the previous chronological district or districts. For more information, contact the county at 29 West Ave. P.O. Box 98 Essex 06426-0098. On the attached map, Middlesex is located at G6. Name of town was Old Saybrook from 1852—54, when a new town of Old Saybrook was separated from this one. The town created in 1852 changed its name to Essex. The probate district called Old Saybrook was created and the old one changed its name to Essex.